This invention relates to containers for receiving body fluid samples, and for containing those samples for subsequent examination to determine the presence or absence of disease in the samples. Generally speaking, such containers will be in tube form and they may or may not be evacuated, depending upon the particular sample being taken. As will be understood by practitioners-inthe-art, evacuated tubes are used in great numbers for taking blood samples, with the tubes containing reagents for reacting with the blood samples for determining the presence or absence of disease. The tubes may also be non evacuated tubes for taking samples for one reason or another. Of course, urine samples may also be taken in both evacuated and non evacuated tubes. While non evacuated tubes are utilized in great numbers, it is preferred to use evacuated tubes for many specific applications for maintaining a seal of the tube prior to use and for facilitating the entry of the sample into the evacuated tube for subsequent testing of the sample.
For evacuated tubes, in particular, it is important to maintain the vacuum over a period of time in order to provide appropriate storage life for those tubes prior to their being used. That is, it is important for the vacuum level to be maintained for a period of time prior to the time when a technician or a nurse uses the tube for receiving a blood sample, for example. Many developments have been made in the past in order to provide plastic tubes for evacuated tube applications. However, plastic tubes have not been developed to the extent where they will maintain an appropriate vacuum for a period of time long enough to be satisfactory for a shelf-life which is appropriate under the circumstances in which such tubes are used. Therefore, it is appropriate and conventional for tubes to be comprised of glass for use as evacuated tubes because glass maintains the vacuum for a much longer or indefinite period of time.
The difficulty, on the other hand, with the use of glass tubes is breakage. With the advent of the highly contagious AIDS virus in many people, it has become extremely important to avoid contamination of technicians, nurses and doctors of blood samples obtained by them from diseased patients.
As will be understood, glass tubes break and/or they may be cracked by inadvertently being struck against some object during the course of the taking of a sample or the course of the sample being delivered from a patient to the laboratory for subsequent testing. It will be understood, further, that such breakage and/or cracking may result in leakage of a diseased blood sample, for example, over the hands of the technician or the person taking the sample or the laboratory technician who is in the course of examining the sample for the presence of disease. If that technician happens to have an open wound, the possibility of acquiring the AIDS virus, or some other disease such as hepatitis, is substantial. Also, broken glass may cut and contaminate, and the pieces must be handled in order to be disposed of. Accordingly, great pains are being taken in the development of any materials utilized for taking and handling samples which contain diseases of this kind and it is this situation to which this invention is particularly directed.
The invention herein utilizes a pre shrunk film disposed over the outer surface of a tube or other container for taking a body fluid sample. That is, a film is pre shrunk over the previously developed glass container. By having the entire outer surface, or a substantial portion thereof covered by a wrapped plastic film, if the tube is broken or cracked, in the kind of accident discussed above, the plastic wrap around the tube contains the sample therein. Thus, even though the sample may not be utilized for subsequent testing for the presence of disease because of the crack or break, at least the technician may contain the sample and dispose of it prior to any dripping or spilling and subsequent contamination. Also, the wrap will shield the user from sharp broken edges, and contains the shattered pieces of glass.
It will be understood, that it makes no difference whether the tube is evacuated or not evacuated in accordance with this invention. The presence of the film firmly adhering to the outer surface of the container holding the sample has the effect of maintaining the general integrity of the container holding a diseased sample so that it may be properly disposed of without any contamination to the user. In addition, the wrap makes the container stronger overall because of the cushioning characteristics of the wrap.
As purely illustrative of a plastic film material which may be used as a shrink wrap over a glass fluid specimen container, one may note that polyvinyl chloride, polyester copolymers or polystyrene films may be utilized for shrink wrapping such containers. One particularly appropriate material is polyvinyl chloride film such as "SkinTight".RTM., a heat shrinkable polyvinyl chloride film supplied by Gilbreth International Corporation, Bensalem, Pa. 18020. Such polyvinyl chloride films obtain the desired shrinking property by first being extruded, and followed by then holding or restraining one dimension of the film while cooling the material, and not restraining the other dimension thereof. This has the effect of pre stressing the material in the direction in which it is held. Subsequently, with the application of heat, the material will then shrink about five to ten percent in the direction not held or restrained while shrinking about fifty five to seventy-five percent in the pre-stressed direction so that it "shrinks down" onto the vessel being covered.
It may be appropriate to apply a heat activated adhesive to the inner surface of the film which will adhere to the vessel being encompassed by the shrink-down film. The heat activated adhesive is printed or applied to the inner surface of the film and when the film is heated for shrinkdown onto the container, the adhesive becomes activated and helps adhere the film to the object being wrapped. Any conventional heat activated adhesive may be used for such application.
As a further feature of the invention, the shrunk down film may be applied to an evacuated container, for example, once the stopper therefor has been put into place and the vacuum applied, holding the stopper in a sealing position. Subsequent application of the plastic wrap which is to be shrunk down may be over both the container itself and it may extend up and over the stopper. By doing so, a further sealing of the stopper/tube interface takes place and a registered serration may be incorporated into the shrink film at the stopper/glass interface in order to develop a tamper proof closure. Such an arrangement may be appropriate, for example, in drug abuse testing, specimen identification and quality control.
Printing may be placed on either side of the shrinkable tube of film material which is to be shrunk down onto the container of interest. For example, a product identification, brand name, company logo may all be included on the inner or outer surface. Moreover, a matte finish or a corona discharged surface may be developed on the outer surface of the film to be shrunk onto the container so as to make the surface appropriate for writing identification information for a sample contained in the container. Furthermore, pressure sensitive adhesive labels may be placed on the outer surface of the shrunk down film so as to accommodate various hospital over labels, for example.
With the foregoing and additional objects in view, this invention will now be described in more detail, and other objects and advantages thereof will be apparent from the following description, the accompanying drawings, and the appended claims.
As purely illustrative of an arrangement of wrapped container which may be used for carrying out this invention, one may note the attached drawings in which several embodiments of such a container are shown utilizing the wrapped container feature of the invention.